Van Andel Research Institute sheds new light on origin of Parkinson's disease

A study led by researchers at the Van Andel Research Institute, published today in the journal Science Translational Medicine, sheds new light on the origin of Parkinson's disease and offers a path for developing new treatments.

The study, which also included researchers from Michigan State University, Northwestern University and Lund University in Sweden, found that the appendix acts as a major reservoir for a protein that's closely linked to the onset and progression of Parkinson's, and that removing the organ early in life reduces the risk of developing the disease by 19 to 25 percent.

That's not to say appendectomies should be used to treat Parkinson's.

Rather, more focus should be placed on reducing excess production of alpha-synuclein proteins and determining how to keep them from escaping the appendix and traveling to the brain, said Viviane Labrie, an assistant professor at Van Andel Research Institute and senior author of the study.

"That way, if there's other areas in the GI (gastrointestinal) tract that could also be involved, which we haven't looked at yet, then you would be treating the entire GI system, not just one place," she said.

An estimated 50,000 people are diagnosed each year with Parkinson's disease, a neurodegenerative disorder in which the brain's cells progressively die, causing tremors, rigidity, slowness of movement and difficulty speaking, according to the U.S. Department of Health and Human Services. About half-a-million people have the disease.

Labrie's study, which was conducted over a two-and-a-half-year period with the help of 11 other researchers, found that the reduced risk of Parkinson's disease was only apparent when the appendix - containing the alpha-synuclein protein - was removed years before the onset of the disease.

Removing the organ after the onset of the disease had no impact on the progression of Parkinson's, the study says.

"We were surprised that pathogenic forms of alpha-synuclein were so pervasive in the appendixes of people both with and without Parkinson's. It appears that these aggregates -- although toxic when in the brain -- are quite normal when in the appendix. This clearly suggests their presence alone cannot be the cause of the disease," Labrie said.

"Parkinson's is relatively rare -- less than 1 percent of the population --so there has to be some other mechanism or confluence of events that allows the appendix to affect Parkinson's risk. That's what we plan to look at next; which factor or factors tip the scale in favor of Parkinson's?"